There has been recently developed a CCD image sensor which provides an image from the detection of infrared radiation. Such a device is described in the article of H. Elabd et al., entitled "High Density Schottky-Barrier Infrared Charge-Couple Device (IRCCD) Sensors for Short Wave Length (SWIR) Applications at Intermediate Temperatures", published in SPIE Vol. 345, Advanced Multi-Spectural Remote Sensing (1982) pages 161-171. In general, these devices include a substrate of single crystalline silicon having formed therein and thereon an array of Schottky-barrier detectors coupled to a charge couple device. In order to protect the CCD image sensors from physical damage and from contaminents in the surrounding environment, it is the practice to place the device in a package which includes an opening through which the detector section of the device is exposed to the object to be sensed. Also, to permit detecting larger object areas, it is desirable to mount a plurality of the devices in the package.
When mounting a plurality of devices in a package, it is desirable to have the devices as close to each other as possible, preferably abutting each other, so that there are no gaps in the image sensed by the overall device. However, this raises problems since if the individual devices are mounted on a base of a package, any variations in the coefficient of thermal expansion of the base with regard to that of the individual devices can cause the devices to either separate from each other or engage each other upon changes in the temperature of the overall package. Also, such differences in the coefficient of thermal expansion could induce undesirable strains in the mechanical and electrical connections between the individual devices and the package base. In addition, the package base should have the characteristics of
(1) being a good conductor of heat, PA1 (2) being capable of masking radiation from undesired sources, PA1 (3) be light in weight, PA1 (4) be sufficiently strong to protect the devices from mechanical damage, and PA1 (5) be capable of carrying interconnecting electrical conductors.